Vulnerability Description
When a user loaded a Web Extensions context menu, the Web Extension could access the post-redirect URL of the element clicked. If the Web Extension lacked the WebRequest permission for the hosts involved in the redirect, this would be a same-origin-violation leaking data the Web Extension should have access to. This was fixed to provide the pre-redirect URL. This is related to CVE-2021-43532 but in the context of Web Extensions. This vulnerability affects Firefox < 94.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 94.0 |
Related Weaknesses (CWE)
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1659155Issue TrackingPermissions RequiredVendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-48/Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1659155Issue TrackingPermissions RequiredVendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2021-48/Vendor Advisory
FAQ
What is CVE-2021-43531?
CVE-2021-43531 is a vulnerability with a CVSS score of 4.3 (MEDIUM). When a user loaded a Web Extensions context menu, the Web Extension could access the post-redirect URL of the element clicked. If the Web Extension lacked the WebRequest permission for the hosts invol...
How severe is CVE-2021-43531?
CVE-2021-43531 has been rated MEDIUM with a CVSS base score of 4.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-43531?
Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Firefox.